Designation via standards:
31309 DIN 720;
27309 GOST 7260-81
The bearing consists of two rings (inner and outer) and rolling elements (tapered rollers) which are connected by a cage. The inner ring with a cage and rolling elements is a CONE. The outer ring is a CUP.
The design of tapered roller bearings suites for the perception of combined (radial and axial) loads. Tapered roller bearings have a split construction: the inner ring with rollers and separator create the unit, that can be mounted separately from the outer ring.